Apparatus for detecting steering torque and steering angle and steering system having the same

Abstract

Disclosed herein are a steering torque and steering angle measurement apparatus, the present invention including a stator fixed to an output shaft, a magnet disposed at the inner part of the stator and being fixed to an input shaft, a torque sensor measuring a steering torque by sensing a magnetic field produced between the stator and the magnet, and a steering angle signal generation part measuring the steering angle by outputting an ON signal ordinary times and outputting an OFF signal at each preset rotation duration of the output shaft when the output shaft rotates, thereby reducing a component number, simplifying a manufacturing process and saving a cost price.

The invention claimed is: 
     
       1. A steering torque and steering angle measurement apparatus, comprising:
 a stator configured to be fixed to an output shaft; 
 a ring magnet disposed at the inner part of the stator and configured to be fixed to an input shaft; 
 a torque sensor measuring a steering torque by sensing a magnetic field produced between the stator and the ring magnet; and 
 a steering angle signal generation part measuring the steering angle, 
 wherein the ring magnet is formed of a ring shape, and disposed such that its polarity alters with an equal interval in a circumferential direction, 
 wherein the steering angle signal generation part includes: 
 a steering angle magnet fixed to a printed circuit board (PCB) to produce a magnetic field; 
 a hall switch outputting an ON signal at ordinary times by being disposed to face the steering angle magnet and sensing the magnetic field of the steering angle magnet; and 
 a rotating member formed with a rotation tooth, and configured to be fixed at the output shaft to simultaneously rotate with the output shaft, 
 wherein the rotation tooth faces the steering angle magnet when the rotation tooth is placed in a nearest position to the steering angle magnet, 
 wherein the rotation tooth is one of an outward projection from the rotating member in a radial direction of the rotating member or an inward indentation of the rotating member in the radial direction of the rotating member, 
 wherein the PCB has a curved shape and is disposed around the rotating member such that the PCB curves around a portion of a circumference of the rotating member, and 
 wherein the torque sensor is fixed to the PCB. 
 
     
     
       2. The measurement apparatus of  claim 1 , wherein the stator includes a stator holder formed of nonmagnetic material, and a plurality of stator teeth coupled to an inner-rim surface of the stator holder. 
     
     
       3. The measurement apparatus of  claim 1 , wherein the stator includes a collector for concentrating a magnetic field formed between the stator and the ring magnet, and wherein the torque sensor is disposed to face the collector. 
     
     
       4. The measurement apparatus of  claim 1 , wherein the rotation tooth is an outward projection from the rotating member in the radial direction of the rotating member. 
     
     
       5. The measurement apparatus of  claim 1 , wherein the steering angle magnet is disposed such that a facet facing the hall switch becomes an N pole or an S pole. 
     
     
       6. The measurement apparatus of  claim 1 , wherein the rotation tooth is an inward indentation of the rotating member in the radial direction of the rotating member. 
     
     
       7. The measurement apparatus of  claim 6 , wherein the inward indentation is a groove with a triangular shape. 
     
     
       8. A vehicle-purpose steering system, comprising:
 an input shaft connected to a steering handle; 
 a measurement apparatus connected to the input shaft; and 
 an output shaft connected to the measurement apparatus, 
 wherein the measurement apparatus comprises: 
 a stator configured to be fixed to the output shaft; 
 a ring magnet disposed at the inner part of the stator and configured to be fixed to the input shaft; 
 a torque sensor measuring a steering torque by sensing a magnetic field produced between the stator and the ring magnet; and 
 a steering angle signal generation part measuring the steering angle, 
 wherein the ring magnet is formed of a ring shape, and disposed such that its polarity alters with an equal interval in a circumferential direction, 
 wherein the steering angle signal generation part includes: 
 a steering angle magnet fixed to a printed circuit board (PCB) to produce a magnetic field; 
 a hall switch outputting an ON signal at ordinary times by being disposed to face the steering angle magnet and sensing the magnetic field of the steering angle magnet; and 
 a rotating member formed with a rotation tooth, and configured to be fixed at the output shaft to simultaneously rotate with the output shaft, 
 wherein the rotation tooth is faced to the steering angle magnet when the at least one rotation tooth is placed in a nearest position to the steering angle magnet, 
 wherein the rotation tooth is one of an outward projection from the rotating member in a radial direction of the rotating member or an inward indentation of the rotating member in the radial direction of the rotating member, 
 wherein the PCB has a curved shape and is disposed around the rotating member such that the PCB curves around a portion of a circumference of the rotating member, and 
 wherein the torque sensor is fixed to the PCB. 
 
     
     
       9. The vehicle-purpose steering system of  claim 8 , wherein the stator includes a stator holder formed of nonmagnetic material, and a plurality of stator teeth coupled to an inner-rim surface of the stator holder. 
     
     
       10. The vehicle-purpose steering system of  claim 8 , wherein the stator includes a collector for concentrating a magnetic field formed between the stator and the ring magnet, and the torque sensor is disposed to face the collector. 
     
     
       11. The vehicle-purpose steering system of  claim 10 , wherein the rotation tooth is an outward projection from the rotating member in the radial direction of the rotating member. 
     
     
       12. The vehicle-purpose steering system of  claim 8 , wherein the steering angle magnet is disposed such that a facet facing the hall switch becomes an N pole or an S pole. 
     
     
       13. The vehicle-purpose steering system of  claim 8 , wherein the rotation tooth is an inward indentation of the rotating member in the radial direction of the rotating member. 
     
     
       14. The vehicle-purpose steering system of  claim 13 , wherein the inward indentation is a groove with a triangular shape.